Field of the Invention
The invention relates in general to a package structure and, in particular, to a substrate structure providing more flexibility.
Background of the Invention
An integrated circuit chip usually comprises a plurality of functional blocks, wherein each of the plurality of functional blocks may need a different environment due to EMI, ESD, or other concerns.
FIG. 1A shows a conventional package structure 10 having a substrate 100. The substrate 10 is divided into a plurality of power/ground domains 101. Each of the plurality of power/ground domains is separated from other power/ground domains. An IC chip 102 is mounted on the substrate 100. An engineer verifies the IC chip 102 in EMI, ESD or other aspects. If necessary, one or more bonding wires will be added to connect some of the plurality of power/ground domains. After verifying and testing, a new arrangement of the plurality of power/ground domain is generated. As shown in FIG. 1B, according to the new arrangement of the plurality of power/ground domains, a new substrate 200 is then designed and fabricated.
However, it is very time-consuming to add bonding wires, as bond wires will have to be added repeatedly to verify different functionalities or different isolation groups. Typically, it takes three or more months to verify the different scopes of an IC chip, extending the cycle time for the engineering development phase.
Therefore, what is needed is a new substrate structure to cut short the cycle time for engineering development phase.